Composite Gel Polymer Electrolyte for High-Performance Flexible Zinc-Air Batteries

Abstract

Enhancing ionic conductivity and electrolyte uptake is of significance for gel polymer electrolytes (GPEs) for flexible zinc-air batteries (FZABs). Herein, a composite mesoporous silica/polyacrylamide (5 wt.% mPAM) GPE is constructed with comparable ionic conductivity to aqueous electrolytes, where the ionic conductivity is up to 337 mS cm⁻¹, and the weight loss after exposing in air 72 h is less than 18%, owing to the excellent electrolyte uptake and continuous ion migration network provided by the mesoporous silica fillers. When used as a quasi-solid-electrolyte, the rechargeable FZAB exhibited high electrochemical performance and structural stability, where the peak power density is up to 162.8 mW cm⁻², and the initial charge–discharge potential gap is as low as 0.62 V, resulting in a long lifespan exceeding 110 h, showcasing the combination of high durability, cost-effectiveness and easy production for practical applications.